As for a direction of the map which map display devices such as a navigation apparatuses display to a display screen, a north-up display mode that displays map north oriented in an upward direction on the display screen and a heading-up display mode that displays a traveling direction in a map oriented in an upward direction on the display screen are widely known. Among those display modes, the heading-up display mode always displays a map with a heading direction adjusted upward, thereby making a relation between a current vehicle position and the map more intelligible compared to the north-up display mode.
In addition, a display screen having two display areas with one area performing the north-up display mode with another area performing the heading-up display mode is proposed in Japanese patent document JP-A-H10-116026 (also patented as U.S. Pat. No. 6,067,502).
As mentioned above, although the heading-up display mode is advantageous in that a relation between the current position and the map is intelligible, the heading-up display mode does not necessarily provide a suitable display for all traveling situations. In other words, in a certain situation, rotating the map to always display the heading direction of the vehicle upward on the screen may make the map less intelligible.